Telephone-receiver.



Patented Dec'. 4, |900.

C. H. NORTH'.

TELEPHONE RECEIVER.

(Appncmon med Nov. 15, 1899.1

(N0 Model.)

/lwenfoze 1' sums Patins co, PnurL UNITED STATES PATENT OFFICE.

CHARLES'H. NORTH, OF CLEVELAND, OHIO, ASSIGNOR TO THE NORTH ELECTRIC COMPANY, OF SAME PLACE.

TELEPHONELRECEIVER..

SPECIFICATION forming part of Letters Patent-No.` 663,196, dated December 4, 1900.

Application liled Nbvember 15, 1899;4 Serial No. 737,048. (No model.)

To all whom, it may concern.:

Be it known that I, CHARLES H. NORTH, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Telephone Receivers, of which the following is a full, clear, andexact description, reference being had to the accompanying drawings.

The object of the invention is to provide a telephonereceiver in which the disadvantages resulting from unequal expansion of the magnet and the insulating-casing shall be eliminated. In accomplishing this I provide the magnet with a cup or h ead which has a flange which, together with the overlying diaphragm, takes between the cap and shell which constitute the casing.

My invention consists, broadly,of the Hangeheaded magnet and cooperating casing and also in the particular form I employ, as hereinafter speciiically described.

The drawings clearly disclose my invention.

Figure l is a central longitudinal section of the receiver complete. Fig. 2 is a section through the magnet cup or head, being at right angles to Fig. l. Fig. 3 is a plan of the head and its containing parts. Fig. L]E is a perspective view of the head alone, and Fig. 5 is a side elevation of the binding-post.

Referring to the parts by letters, A represents the casing-shell, and B the cap screwing thereto, these parts being preferably made of hard rubber.

The magnet is carried by the cup or head C, which has an annular projection or iiange c, taking between the cap and shell. The diaphragm D lies on a washer E, which lies on this annular iiange c, and the cap bearing down on the upper edge of the diaphragm locks the diaphragm and head-C together. This renders the magnet independent of the unequal expansion between the shell and magnet-bars. Moreover, the whole magnet is self-contained and is easily installed in the casing or removed therefrom.

The magnet-poles are designated F and F. Each is surrounded by electric winding G, below which the poles are bent outward at right angles, as at F2. These outwardly-projecting portions rest on an insulating-disk H, which lies within the head C. The base of the permanent magnet consists of a plurality of magnetized iron rings, four being shown, (designated J' J2 .I3 J4.) By making the magnet thus in separate rings instead of one integral piece of iron wasteful Foucault currents are avoided, as well known. Above the top ring .I4 is the cover-ring of non-magnetic material K. The Whole is secu rely locked together by the two screws L L', which extend from below the head C through the insulating-disk H and through the magnetic rings into the cover-ring K.

Secured to the under side of the disk H within an opening c' in the head C are the binding-posts M and M. Each of these-bind-` ing-posts is formed, as shown at Fig. 5, and consists of the plate m, (which has holes through which screws pass, securing it to the disk H,) the barrel m', which has an integral stud m2 passing through the plate m and riveted thereto, and the strip m3, which surrounds the stud m2 and is tightly clasped between the barrel and the plate. The strips m3 are bent to project upward parallel with the surface of the barrel, and they thus eX- tend through openings in the disk H and lie close to the magnets, and the terminal wires of these magnets are secured one to one pin and one to the other, being soldered thereto. Suitable set-screws m4, screwing into the barrels m, lock in the recesses of the barrels the terminals p of the iiexible cord P, which eX- tends freely out of the shell through the opening a. It will thus be seen that the permanent and electro magnets and the bindingposts are all carried by the hanged head C. The expansion of the casing as a disturbing element is eliminated, while the parts being all self-contained are easily adjusted in the first place irrespective of the casing and are easily removable therefrom.

Having described my invention, I claim- 1. In a telephone-receiver, a casing consisting of a shell and a cap secured directly thereto, combined with a magnet within the casing and supported by having a projection clamped between the cap and shell, and a diaphragm supported in proximity to the mag-` net-pole.

IOO

2. In a telephone-receiver, the combination with the shell, of a magnet having a head thereon, and an annular flange or rim on the head adapted to engage the edge of the shell, a diaphragm overlying the magnet and supported on said flange or rim, anda cap overlying the diaphragm, and secured directly to the shell, whereby the diaphragm and magnet are secured together in position.

3. In a telephone-receiver, in combination, a cup-like head, an insulating-disk Within the head, a pair of electromagnets havingv cores extending outward at substantially right angles and lying on the upper surface of the disk, an annular permanent magnet lying within the head engaging with said outwardlytu rned cores, an annular nonmagnetic coverring lying above the magnet, and screws passing through the head and screwing into such non-magnetic ring whereby said screws lock the magnet, the head, tne insulating-disk, and the cover-ring all together, substantially as described. A

4. In a telephone-receiver, in combination, the head C having the opening o through its bottom, an insulating-disk within the head extending across said opening, electromagnets Withinsaid head, an annular permanent magnet within the head engaging with the cores of the electromagnets, means for locking the parts together, a pair of bindingposts secured to the under side of the insulating-disk Within the bottom opening in the head,said binding-posts being connected'with the terminal wires of the electromagnets,sub stantially as described. i

5. In a telephone-receiver, in combination, a head C, an insulating-disk I-I Within the same,an electromagn et,and a permanent magnet within said head above said disk, and a binding-post M secured to the under side of the disk, said binding-post consisting of the plate m, the strip m3 lying in engagement with the plate and extending through an opening in the disk andhaving secured to it the magnet-wire and the barrel m having the rivet-st ud fm2 extending through the strip and riveted to the plate m, substantially as described. Y

6. In a telephone-receiver, in combination, a casing consisting of ashell and a cap screwing thereonto,a magnet within the casing having a flanged head the flangey of which lies between the shell and cap, a diaphragm lying between the flange and cap, said head and diaphragm being locked in place by the cap, a pair of binding-posts insulatingly carried by the head within the casing, and a pair of electric conductors secured to said bindingposts and passing loosely through an opening in the shell, substantially as described.

In testimony whereof I hereunto ax my signature in the presence of two witnesses.

cHARLEs H. NORTH.

Witnesses:

ALBERT H. BATES, PHILIP E. KNoWLToN. 

